How to sync Desk & CRM contact via api

How to sync Desk & CRM contact via api

Hello, 

Is there is a way to sync contact in Desk using for example CRM id,
like what we have in Zoho Books "Import a customer using CRM contact ID".

I know that there is Integration in the marketplace but this is not what I'm asking for or what I need.
I tried to update "zohoCRMContact" field but nothing changed.

So, instead of using Integration is there is a way to sync Desk & CRM contacts?